When pressurizing a fluid, whether a liquid or gas, cooling is often desirable, or required. For example, in the case of compressing a gas, it is common to cool the gas upstream of a compressor inlet to increase efficiency, or, in the case of multiple-stage compressors, cooling the gas between one or more of the stages. In the case of pumping a liquid, cooling can be required to maintain the liquid below a maximum allowable temperature. For example, in a hydraulic drive system, hydraulic fluid often must be maintained below a certain temperature to avoid overheating the fluid and degrading hydraulic performance and/or possibly causing the hydraulic fluid to decompose. Cooling can also be desirable in liquid pumping and gas compression applications for other reasons, such as the need to maintain thermal equilibrium of both hot and cold fluids or to maintain system fluids below any maximum allowable operating temperatures for system components.